Crimping tool with adjusting means



Aprll 10, 1962 H. KELLER ETAL 3,023,775

CRIMPING TOOL WITH ADJUSTING MEANS Filed June 4, 1959 INVENTORS HERMANKELLER CLIFFORD R. WALDRON ATTOR Ns United States PatentO 3,028,776CRIMPING TOOL WITH ADJUSTING MEANS Herman Keller, Sidney, and CliffordR. Waldron, Unadilla, N.Y.,,assignors to The Bendix Corporation, acorporation of Delaware Filed June 4, 1959, Ser. No. 818,068 2 Claims.(Cl. 81-15) This invention relates to a tool for indenting a ferrule;such tool is useful, for example, in the fastening of a cable or wire toa lug or contact.

The invention has among its objects, the provision of a novel improvedindenting tool of the type described, which is characterized by theaccuracy and uniformity of the indented products produced thereby.

A further object of the invention lies in the provision of an improvedindenting tool having an indentor advancing cam means pivotally mountedwith respect to the indentor mounting and guiding means.

Still a further object of the invention lies in the provision, in a toolof the type indicated immediately above, of means for adjusting theinner terminal position of the indentors corresponding to the final,inner angular position of the indentor advancing and indentor guidingmeans relative to each other.

Yet another object of the invention lies in the provision of anindenting tool of such character, that after the indentors have oncebeen advanced forcibly to contact a workpiece such as a ferrule, theindentors can not thereafter be retracted to release the workpiecebefore they have completed the full path of their operative stroke.

The above and further objects and novel features of the invention willmore fully appear from the following description when the same is readin connection with the accompanying drawings. It is to be expresslyunderstood, however, that the drawings are for the purpose ofillustration only, and are not intended as a definition of the limitsofthe invention.

In the drawings, wherein like reference characters refer to like partsthroughout the several views,

FIG. 1 is a view in side elevation of a preferred embodiment ofindenting tool in accordance with the invention, the indentors of thetool being shown in their fully advanced, inner position with theoperating arms of the tool advanced into their inner, most nearlyadjacent position; 7

FIG. 2 is a fragmentary view in vertical section generally through theaxis of the head of the indenting tool, the section being takengenerally along the line 2-2 of FIG. 1, FIG. 2 showing a pin contact ofa separable electrical connector within the tool and in the condition inwhich the ferrule of such contact has been fully clenched upon a leadvw're connected thereto;

FIG. 3 is a fragmentary view in vertical section through the tool headshown in FIG. 2, the section being taken generally along the line 3--3of FIG. 2, certain of the parts being shown in elevation, the indentorsbeing shown in their inner, fully advanced position;

FIG. 4 is a fragmentary view in vertical section similar to FIG. 3 butwith the indentors, and the indentor moving arms, occupying their outer,fully opened positions, the figure also showing, in phantom lines, anintermediate position of the parts wherein the indentors and theindentor-operating arms are prevented from outward movement;

FIG. 5 is a view in vertical section through the indentor mountingelement of the head of the tool, the section being taken along the line5-5 of FIG. 2;

FIG. 6 is a view in vertical section through the tool showing the upperend of an indentor-operating arm, the section being taken along the line6-6 of FIG. 2;

FIG. 7 is an enlarged view in end elevation of the serrated ring memberdesigned to interfit between the serrated surfaces of the portions ofthe apparatus shown in FIGS. 5 and 6 whereby to effect a fine angularadjustment between such parts; I

FIG. 8 is a view in side elevation of one embodiment of connectorcontact and wire leading thereto, which may be assembled by oneembodiment of the indenting tool of the present invention; and

FIG. 9 is a view in elevation of a second embodiment of contact and leadwire assembly which may be made by a further embodiment of the indentortool of the present invention. I

The indentor tool of the invention in the embodiment thereof shownherein is particularly adapted for assembling connector contacts, suchas those shown in FIGS. 8 and 9, upon their lead wires. Such connectorsare adapted for use in separable electric connectors of the typedisclosed and claimed in application Serial No. 808,611, filed April 24,1959, by George I. Swanson. In such contact assembly, theclenching orindentingof a ferrule on the contact upon the lead-wire extendingtherei-nto is relied upon for both the sole mechanical and soleelectrical connection between the wire and the contact ferrule. Inorder'that-such connections shall have'the desired mechanical strengthand electrical conductivity, both initially and after long periods ofarduous service, the connecting ferrule of the contact must be held toclose tolerances in machining, and the clenching or indenting operationmust closelycontrolledj Thus, if the degree of indention of the ferruleupon the wire should be inadequate, the resulting joint will not onlylack the desired mechanical strength, but it will leave a somewhat openstructure within the indented ferrule, assuming the wire is of themulti-strand type, in which the strands are only loosely packed, therebyallowing the. markedingress of air into the joint. If, however, thedegree of clenching or indention of the ferrule wall is too great,either on one or all sides thereof, the side wall of the ferrule will belocally drawn, reducedin gauge, and thereby weakened or in some casesevenzpunctured. It will be seen, therefore, that the ferrule indentingoperation must be carried out with care, and with precision apparatus,if such manner of connection of electrical fittings and lead wiresthereto is to be satisfactory.

The embodiment of indenting tool shown herein has proved to beparticularly satisfactory for use by work-' men engaged in installing insitu electrical connectors in cables. It will be understood, however,that in some instances it may be desired to mount the headof anindenting tool made in accordance with the invention on a fixed support,and to rotate the mainparts of the head relative to each other as bypower means rather than by handles as shown.

The head of the clenching or indenting tool of'thc invention intheembodiment shown is generally designated by the reference character10. In describing the tool and the parts which form it, the horizontaldirection to the right in FIG. 2 will be termed the forward direction,and

' ing element 12 has an annular flange 17 fitting within a} similarlyshaped seat in the wall of cam housing 11. A split spring ring 19,snapped into the seat at the rear of flange 1 7,-retains element 12within the cavity in cam housing 11.

As shown more particularly in FIGS. 3 and 4, element 12 has four equallyangularly spaced radially directed guideways 20, lying at the forwardend of element 12 adjacent wall 15 thereof. Radially reciprocable inguideways 20 are four clenching or indenting tools 21, each indentor 21being very accurately guided in its respective guideway. The outer endsof tools 21 are partially circular cylindrical, as shown at 22, ends 22having sliding engagement with the respective ones of the four camsurfaces 24 on the inner periphery of cam housing 11. Between theradially innermost end of each of cam surfaces 24 and the radiallyoutermost end of the next adjacent cam surface, there is located a partcircular cylindrical pocket 25 which accurately receives the outer end22 of its respective indenting tool 21 when such tools are retractedinto inoperative position, as shown in solid lines in FIG. 4. Indentingtools 21 are constantly urged outwardly into engagement with the cams 24and/or the pockets 25 by a split spring ring 26, which fits within slots27 in the forward faces of the indentors as shown in FIGS. 3 and 4. Thespring ring 26 is of such relaxed configuration that it constantly tendsforcibly to expand radially outwardly of the position shown in FIG. 4.

The cam housing 11 of the head of the tool has an extension 29 integraltherewith, there being a handle extension 30, conveniently formed ofbent sheet metal, attached thereto by bolts 31. Adjustably secured toinden tor-mounting element 12 is a second, handle-forming arm, composedof an upper, centrally apertured portion 32 having an extension handle34 connected thereto as bolts 35. The upper apertured end portion 32 ofthe second handle is snugly but rotatably received over a central hollowtrunnion-like member 36 which projects rearwardly from element 12.Portion 32 is adjustable angularly with respect to member 36, and thuswith respect to element 12, by the following mechanism. The rear face ofelement 12 is serrated as shown more clearly in FIGS. and 7. Suchserrations, which are designated 37, are equally angularly spaced aboutthe axis of element 12; conveniently there may be 24 serrations 37.Fitting accurately over member 36 and rotatable thereon is a serratedadjusting ring 39 having serrations 41, on its forward surface, whichmesh accurately with serrations 37, that is, there are 24 equally spacedserrations on the forward face of ring 39. The rear face of ring 39 hasa plurality of equally angularly spaced serrations 40 thereon, suchserrations differing slightly in number from serrations 37 and 40.Conveniently there may be 23 serrations 40 on ring 39. The forward faceof element 32 is provided with a plurality of serrations 42 of the sameshape, serrations 42 being equal in number and complementary in shape toserrations 41. After adjustment of the parts, in the manner to bedescribed, elements 32, 39, and 12 are maintained tightly together withtheir serrated surfaces in mesh by means of a nut 44 threadedly engagedwith the threaded outer end of element 36, and by a spring washer 45interposed between nut 44 of the rear surface of element 32. In theembodiment disclosed, spring washer 45 is laminated and in relaxedcondition is bent or dished somewhat along one diameter.

The tool head has a connector-locating means in the form of a stud 46having the forward end thereof provided with a forwardly open axial bore47. Stud 46 accurately fits within the central axial bore 49 in member36, and is held accurately by means of a flange 50 on member 46, and anut 51. As shown, flange 50 engages the end of member 36; the nut 51 hasan annular rear flange thereon overlying flange 50 and thrusting member46 forwardly. The axial length of bore 47 in member 46 is such that whena contact such as that shown at 52 in FIG. 2 is placed with itsoperative end in engagement with the inner end of bore 47, the ferruleon the contact is positioned in the proper transverse plane axially ofthe head of the tool to be operated upon by the inner ends 54 of tools21. It will be obvious that contacts of different effective lengths maybe operated upon by the tool by the substitution of another locatormember 46 having a bore 47 therein of the diiferent required length.

The position of nearest approach of handles 30 and 34 of the toolrelative to each other is determined by the adjusted position of a stopstud 55, which is threaded into a bore 56 in handle portion 29, as moreclearly shown in FIG. 1. Preferably, as in the construction shown, theslotted outer end of stud 55, by which it is adjusted, lies hiddenbeneath the upper part of handle extension 30, thereby to preventtampering with the adjustment of the stop.

The embodiment of tool shown is provided with a means whereby, once theindentors have been advanced into firm engagement with a ferrule, thetool can not be again opened until the indentors have completed theiroperative stroke. In the illustrative embodiment, such means takes theform of a pawl 57, which is pivotally mounted upon arm 32 by means of apivot pin 59. Pawl '57 is constantly urged into the position shown infull lines in FIG. 3 and in phantom lines in FIG. 4 by means of a coiltension spring 60 having the bottom end thereof attached to arm 32 at 61and the upper end thereof attached to the lower end of pawl 57 at 61. Insuch position the upper, pointed operative end 64 of pawl lies in thecentral longitudinal plane of arm 32.

The end 64 of the pawl selectively cooperates with three downwardlyextending serrations 65, 66, and 67, the point 64 of the pawl, when thetool is open as shown in FIG. 4, lying to the left of serration 65, and,when the tool is fully closed, lying to the right of serration 67. Whenarm 32 is swung to the right from its full line position shown in FIG.4, the upper end 64 of pawl 57 snaps into the valley between serrations65 and 66 or if such motion is continued, into the valley betweenserrations 66 and 67. In either of such two latter positions, the pawl57 is swung counterclockwise, as shown in phantom lines in FIG. 4, sothat the pawl 57 now effectively prevents or blocks retrograde movementof arm 32. It is only when the arms 30 and 34 have been swung togethersulficiently to cause point 64 of the pawl to clear serration 67, asshown in FIG. 3, that the arms 30 and 34 again become free to be movedapart.

The arms of the tool are constantly urged apart into tool-open positionby the spring 69 acting therebetween, as shown in FIG. 1. The arms ofthe tool must be fully open to accept the largest diameter of theferrule or other part being crimped. Undue separation of the arms,should the arms be allowed to spring apart under the action of spring69, is prevented by a cross-pin 70 engaging bent tang portion 71 on thelower end of spring 69.

In FIGS. 8 and 9 there are shown alternative connectors which may beoperated upon by the embodiment of the tool shown. In FIG. 8 the contactis that shown at 52 in FIG. 2, such contact having one ferrule 72engaging the end of the lead wire 73. Thus the inner, operative ends 54of the indentors 21 need have indenting surfaces lying generally in onehead transverse to the axis of head 10. In FIG. 9, on the other hand,the contact 74 has two ferrules, one, shown at 75 engaging the forwardend of wire 76, and the second, shown at 77 being larger and clenchedupon the end of the insulation 79 on the wire 76. In forming theassembly shown in FIG. 9, the embodiment of tool shown will have itsindentors provided with two clenching zones, the rear zone clenchingferrule 75 upon the wire 76, and the forward zone clenching ferrule 77upon the insulation 79.

The described construction of the tool, including the adjustable stop 55and the adjusting means including serrated ring 39 acting between arm 32and element 12, permit the tool to be accurately adjusted, whennecessary, to compensate for the wearing of the elements of theindenting tool, including the outer end surfaces 22 on the indentors 21and cam surfaces 24 on cam housing The indentcrs 21 and the spring 26are assembled in guide element 12, and such assembly is installed in camhousing 11, being retained therein by snapping the split Spring ring 19into the cavity rearwardly of element 12.

The pawl 57 and spring 6% are then mounted upon arm 32. Adjusting ring39 is then telescoped over element 35, ring 39 being placed so that itsteeth 41 mesh with teeth 37 on the rear face of element l2. Arm 32 isnow telescoped over element 36, and is positioned so that it forms anangle of about 28 with handle portion 29. With arms 2? and 32 held insuch position relative to each other, the curved spring washer 45 isinstalled over element 36 and is held in place by the nut 44, which istightened finger-tight at this time. The adjustable stud 55 is nowinstalled, and is screwed inwardly so that its inner end lies spaced adistance of .062 to .004 inch from arm 32 when the point 6 of pawl 57just barely snaps past the last tooth or serration 67 on the body of camhousing 12.

This can best be done by first adjusting stud 55 so that the arm 32 cannot be closed enough for the pawl 57 to snap past the last tooth 57.Then, holding the tool closed, the operator slowly backs out the stud 55until the pawl 57 snaps clear of tooth 67. The adjustment is checked byinserting a .904 inch feeler gauge between the screw 55 and arm 32 andthen closing the tool. The pawl should not snap clear of tooth 67. Thesame operation is repeated using a .002 inch feeler gauge. The pawlshould now snap clear of tooth 67. The tool should then be opened andclosed several times and rechecked to make sure that its action isconsistent.

After a justment of the set screw 55 is completed, a piece of maskingtape is attached over the pawl 57 to prevent it from contacting theteeth 65, 66, and 67 on arm 32 while the indentors are adjusted. Theindentor setting is now checked, and the distance between the inner endsof the indentors is measured with the tool closed. it such dimension isgreater than the desired setting, nut 44 is loosened and the adjustingring 39 is turned one click relative to arm 32 and element 12. Whileholding ring??? in its new position, nut 44 is re tightened, after whichthe distance between the inner ends of the indentors 2:1 is checked withthe tool closed. It will be understood that such turning of adjustingring 39 one click relative to arm 32 and element 12 will have adjustedthe terminal position of element 12 relative to cam housing 11 throughan angle approximately equal to 39 minutes, that is, the differencebetween of 360 and of 360.

Cam surfaces 24 are so designed that when arms 39 and 3d are moved onetooth in either direction of the adjusting ring the effective result isa movement of the indentors equal to .0026 inch. If, however, thedistance between the inner ends of the indentors, with the tool closed,is less than the desired dimension, nut 44- is loosened and the arms 3%and 34 of the tool are closed and en opened one tooth each way on theadjusting ring 39 for each .0026 inch the distance between the innerends of indentors is below the desired setting.

When the desired setting is obtained, nut 44 is tightened to apredetermined degree as by using a torque wrench thereon. The maskingtape is now removed from pawl 57, and the assembly of the tool head iscompleted by installing the contact locator 46 and the nut 51. Handles3t) and 34 are now attached to arms 29 and 32 of the tool; the tool isnow completely assembled and ready for use. The tool may be readjusted,when necessary, to compensate for wear on the indcntors, cam ring, etc.,whereby to restore the tool to its initial accurately adjustedcondition.

Although only one embodiment of the invention has been illustrated inthe accompanying drawings and only two embodiments thereof have beendescribed in the foregoing specification, it is to be especiallyunderstood that various changes, such as in the relative dimensions ofthe parts, materials used, and the like, as well as the suggested mannerof use of the apparatus of the invention, may be made therein withoutdeparting from the spirit and scope of the invention as will now beapparent to those sltilled in the art.

W rat is claimed is:

l. A tool for crimping a ferrule upon a wire, comprising a tool headcarrying a plurality of ferrule-indenting tools for movement inwardlytoward and outwardly away from each other, a cam means rotatable withrespect to the tool head for advancing the tools inwardly in a workingstroke, means for drivingly rotating one of the cam means and the toolhead with respect to the other, and means for adjusting the angularrelationship between the driven element and the driving means therefor,said last means comprising a ring member interposed between the drivenelement and the driving means, opposite sides of the ring membercarrying a plurality of uniformly spaced teeth, the teeth on the twosides of the ring memher being different in number, teeth on the drivenelement and the driving means meshing with the teeth on the respectivesides of the ring member, and means for holding the driving element, thering member, and the driven element together in driving relationship.

2. A pliers-type tool for crimping a ferrule upon a wire, comprising acircular tool head carrying a plurality of generally oppositely disposedferrule-indenting tools for movement inwardly toward and outwardly awayfrom each other, a barrel means disposed about the periphery of the toolhead and carrying cam ramps cooperating with the outer ends of thetools, the barrel means being rotatable with respect to the tool headabout the axis thereof for advancing the tools inwardly in a workingstroke, levers constituting handles connected to the tool head and thebarrel means, stop means acting between the levers for determining theterminal positions of the levers when thetools are in their innermostposition,

' and means for adjusting the angular relationship between one of theelements consisting of the barrel means and the tool head and itsrespective lever, said last-named means comprising a ring memberinterposed between the i References Cited in the file of this patentUNITED STATES PATENTS 918,065 Low Apr. 13, 1909 1,262,621 Beacham s Apr.16, 1918 2,086,400 Brenizer July 6, 1937 2,696,747 Bergan Dec. 14, 19542,753,742 Buchanan July 10, 1956 OTHER REFERENCES I American Machinist,pages l689, Jan. 22, 1931.

